Electric controlling apparatus



F. G. LOGAN 2073,38

ELECTRIC CONTROLLING APPARATUS Filed Feb. 9, 1935 6 Sheets-Sheet l April 27, 1937.

3 CO/V TAL HANDLE F05/ 7"/0N 6 Sheets-Sheet 2 2" /5 LNA F. G. LOGAN ELECTRIC CONTROLLING APPARATUS Filed Feb. 9,

20a A94 A9Z wl /515 /9o )zg INVENTOR (ATTORNEY April 27, 1937.

F. G. LOGAN April 27, 1937.

ELECTRI C CONTROLLING APPARATUS Filed Feb. 9, 1935 6 Sheets-Sheet 5 YL ...l

INVENTOR z BY Kg /ZMA ,f'xTToRNEYl April 27, 1937. FA G. LOGAN 2,078,880

ELEGTRI C CONTROLLING APPARATUS Filed Feb. 9, l935 6 Sheets-Sheet 4 ATTO R N EY April 27, 1937. F. G. LOGAN 2,078,880

ELECTRI C CONTROLL ING APPARATUS Filed Feb. 9, 1955 6 Sheets-Sheet 5 F/G. /O

INVENTOR ATTORNEY lApril 27, 1937. F. G. LOGAN ELECTRIC CONTROLLING APPARATUS Filed Feb. 9, 1935 6 Sheets-Sheet 6 i INV-ENTOR jm@ ATToRNz-Y Patented Apr. 27, 1937 2,078,880 l ELECTRIC CONTROLLING APPARATUS Frank G. Logan, Mount Vernon, N. Y., assigner to Ward Leonard Electric Company,

ration of New York Application February 9, 1935, Serial No. 5,719

29 Claims.

This invention is particularly' applicable to the control of consumption circuits wherein the voltage applied thereto is varied over a wide range, such as in the case of dimmer control of lamp circuits for stage productions. Reactors are commonly used for effecting this variation of lamp circuit voltage wherein current from the alternating current source is passed through one or more windings on the reactor core in series with the lamp circuit. 'Ihe lamp circuit voltage is ad- 'justed to the desired different values by changing the value of a direct current passing through another Winding on the reactor core. This results in changing the magnetic ilux of the core and thus changes the reactance of the alternating current windings resulting in correspondingly changing the voltage applied to the lamp circuit. The value of the controlling direct current is changed by some adjustable means, such as a control handle or sliding cont-act. When the number of lamps connected to the consumption circuit, or the load, remains constant, the position of the control handle will always be the same for securing the same consumption circuit voltage or the same lamp brilliancy, assuming the voltage of the source to remain constant. When, however, thevnumber of lamps connected to the consumption circuit, or load, is changed, the voltage applied to the consumption circuit becomes quite different for a given position of the control handle. Furthermore, under any lamp load, there results a considerable departure of the voltages applied to the consumption circuit along the range of adjustment, from the most desirable or ideal lamp voltage curve with reference to the successive steps of movement of the controlling handle. It thus follows that when the lamp load on one of these controlled circuits, or on any number of them is changed for obtaining diierent lighting eiects, the operator finds that for corresponding positions of the controlling handle, the resulting lamp voltage and lamp brilliance varies greatly. The operator is likewise unable to secure the ideal lamp voltage over the lull range for any load. Where a multiplicity of these lamp circuits is to be variably utilized with dierent loads in different set-ups of sequential scenes, it is impossible for the operator to preset the controlling handle for each circuit to give the required voltage and lighting eifect, owing to the practical diiiculties of attempting to variably preadjust the position of the control handle for different lamp loads. Likewise with the usual control system, he cannot obtain the ideal lamp voltage curve under any load.

The main object of the present invention is to provide an improved method of control and automatic controlling means for securing the same lamp voltage, or consumption circuit voltage, or load condition, from each corresponding position of the control handle, regardless of the value of the load, or change in number of the lamps in circuit within the capacity range of the reactor. Another object is to attain the ideal lamp voltage curve, or a close approximation thereto, throughout the range of control for any load. Other objects are to accomplish these purposeseflicientlyvand by means of apparatus which is comparatively simple, inexpensive and dependable with long continued use. Another object is to reduce the size and cost of the main controller which becomes permissible because the auxiliary controlling means secures automatic control of the minimum and maximum controlling current under all loads and thus avoids the necessity of extra size of the main controller otherwise required for obtaining desired results at the extremes of adjustment. Other objects and advantages will be understood from the following description and accompanying drawings.

Figure 1 is an explanatory chart; Fig. 2 is a diagram showing one embodiment of the invention; Fig. 3 is a similar diagram with a modified form of control; Fig. 4 is a diagram of another embodiment of the invention; Fig. 5 is a, diagram similar to Fig. 4 with a modified form of control; Fig. 6 is a diagram of a different type of control embodying the invention and Fig. 7 is a diagram of a modified form thereof; Fig. 8 is a diagram of another embodiment and Fig. 9 a modified form thereof; Fig. l is a diagram of still another embodiment of the invention and Figs. 11 and 12 are diagrams of modied forms; and Fig. 13 is a diagram similar to Fig. 12 and in which separate cores are used in the auxiliary controlling reactor.

Referring to Fig. l, the abscissae represent the position of the dimmer control handle and equal increments of saturating current and the ordinates represent the volts applied to the lamp circuit. The line A represents an example of 'an ideal lamp voltage curve, being shown as a straight line and giving the same increase ln volts applied to the lamp circuit for each step of the control handle. This ideal curve may be different for particular cases but the line A may be assumed as the most desirable for the present case. The curve B shows the actual results obtained when the lamp load on the circuit was comparatively small and when using the customary reactor control system. Here the lamp voltage is at about volts when the control handle is in position 21/2. Thus in the more advanced handle positions there is practically no control of the lamps and there is altogether a too pronounced change of lamp voltage in the initial positions. The curve C shows the actual results obtained with twice the load of curve B. Curv: C shows 100 volts is attained before position 5 of the control handle is reached giving no practical control beyond that position. Likewise the control is too pronounced in the initial positions. 'Ihe curve D shows the results obtained with the optimum lamp load and the circuits specially adjusted to give the best results for that load. Even then the lamp voltage change is too pronounced at the middle handle positions and too small in the outer positions. Obviously, with the widely different lamp voltage curves resulting from adjustment o! the control handle under the different load conditions, the lighting eiIect is quite diiierent for corresponding positions of the handle and cannot even obtain the ideal curve with the optimum load. By means of the present invention, the method of control and apparatus used results in bringing the lamp voltage curve under all load conditions to approximately coincide with the ideal lamp voltage curve for all positions oi.' the control handle.

In carrying the present invention into effect. the method employed consists in utilizing or specially creating a selected reference lamp voltage for the different positions of the control handle, such as the line A oi' Fig. 1, and then causing the voltage applied to the consumption circuit to conform thereto, or very nearly thereto, by utilizing the diiierence between the reference voltage and lamp circuit voltage for yielding a resultant current which in turn controls suitable compensating means. 'Ihis voltage or potential difference is comparatively slight in order to secure the desired compensating eiiect with the result that the lamp circuit voltage may be readily kept, in practice, within one or two volts of the reference voltage, or ideal lamp voltage, for all positions of the control handle, even under change of load.

One form of apparatus ior practicing this invention is disclosed in Fig, 2 wherein the alternating current source I, which may be any suitable source, supplies current to the consumption circuit 2, indicated -as having a lamp load. A main controlling reactor is shown having a core l which is indicated for simplicity as of the three-legged type. On the outside legs are wound the usual alternating current windings l, l' in series with each other and with the load. Obviously, when the reactance of these windings is changed by control of the magnetic ilux of the core, the voltage applied to the consumption circuit will be changed in a manner well understood by those skilled in the art. A source 5 of direct current supplies a winding 8 on the middle leg of the core 3 which may be termed a saturating winding. The source 5 may be any suitable source and may be derived from the alternating current source l but is shown as a battery for simplicity. A resistance 1 is connected across the direct current source and one terminal of the winding 8 is connected to the adjustable contact 8 engaging the resistance 1. In the usual reactor control system the winding 6 serves as the main controlling direct current winding, current therein being adjusted by the movable contact 8, corresponding to the control handle above referred to. As already explained in connection with Fig. l, the lamp circuit voltage will vary greatly, under diii'erent lamp loads, and widely depart from the ideal lamp voltage curve for corresponding positions of the control contact I unless some compensating means be employed.

In the present instance, the ampere-turns of the winding 6 are made considerably less than those of the usual direct current control winding of the reactor and is made so much less that at no time will the voltage applied to the consumption circuit in any position of the control handle I, attain the values represented by the ideal lamp voltage curve. 'Ihat is to say, the lamp voltage curve resulting from the use oi winding I alone would, at all points. be below the ideal lamp voltage curve. In order to bring the lamp voltage up to the desired value for each position of the control handle, another uni-directional current winding I is shown added to the middle leg of the reactor core and is wound in such direction, as indicated by the arrows on the middle leg of the core. as to act cumulatively with the excitation of the winding t. The current in the compensating winding 9 is dependent upon the amount which the lamp circuit voltage departs from the selected reference voltage curve which diilerence is always comparatively small.

In order to create the reference voltage so that it will be related to the consumption voltage to give the desired control of the lamp circuit voltage for all positions of the control handle. an auxiliary reactor Il which may be comparatively small, is provided which in turn supplies a special reference load Il. Ihe reactor I0 is shown as having a three-legged core for simplicity and as having the outside legs enveloped by alternating current windings ila and Ib which are connected in series with each other and with the load II across the supply lines of the source i. The middle leg of the core carries a direct current winding llc which is connected in parallel with the winding 6 between the control handle l and the other side of the resistance 1. The reference load Il isailxedloadandmaybemadeupofsuch combination of resistive, inductive and capacitive devices, as will give the desired reference control voltage for making the consumption circuit voltage coincide with, or closely conform to. the desired circuit voltage curve for all positions of the control handle. The load Il is of comparatively small value and a lamp, resistor, inductor and condenser is represented as a general indication oi' making up the load of such character as will give the desired reference voltage, the composition and adjustment of such load being arrived at in a manner well understood in the art. This reference load is formed not only to give a required voltage as a reference voltage to the consumption circuit voltage throughout the range of control, but also to give a desired phase relationship oi' its voltage to that of the consumption circuit.

In order to relate the reference voltage tn the consumption circuit voltage and to utilize their difference for securing the desired controlling current in the winding l oi' the main reactor, one side of the load Il is connected directly to one side oi' the consumption circuit by the lead l! and the other side o! the load il is connected to the other side of the consumption circuit through a full wave rectier which will deliver a current to the winding 9 depending upon the potential and phase dilIerence applied to the rectifier. Any suitable form of rectifier may be used but for simplicity a copper-oxide rectier I3a, I3b, I3c, I3d, is indicated connected respectively in'each side of a bridge connection. 'I'he opposite apexes of the bridge are connected respectively to one side of the consumption circuit and to one side of the reference load so that the rectifier is subjected to the difference in potential between them. The other opposed apexes of the bridge are connected to the winding 9. It will be seen that when the line I4 of the consumption circuit has one polarity, current will pass therefrom through the rectier I3a, winding 9 and through rectier I3c to the line I5 of the reference load. When the polarity of the line I4 is reversed, current will pass from the line I5 through the rectier I3b, winding 9 and through rectifier I3d, to line I4. Obviously, the magnitude of the current which Will flow in the control winding 9 will depend upon the relative potentials of the points I4 and I5.

In understanding the operation, it should be remembered that if the control winding 6 were l used without the cooperative effect of the winding 9, the voltage of the consumption circuit would always be such as to give a consumption' circuit curve below the desired curve in all positions of the control handle 8; and the voltage of the reference load for all positions of the control handle will conform closely at all times to the ideal lamp circuit voltage. Let it be assumed that the handle 8 be placed in one of the intermediate positions. At that time the current in the winding 6 is not enough to suiiiciently saturate the core 3 to bring the voltage of the lamp circuit up to the desired amount. Consequently, a potential difference exists between points I4 and I5 in the consumption circuit and the reference load which will cause a resultant controlling current to flow in the winding 9. As this current has a cumulative effect with that of the winding 6 on the saturating flux of the core 3, the voltage applied to the lamp circuit will be correspondingly increased. As, the resistance of the compensating circuit, including the winding 9 and the rectiers,

may be made low, the current in the compensating winding 9 may be of such value as to increase the voltage applied to the consumption circuit to the required amount, or very close thereto, with only a slight diierence in potential between the points I4 and I5; and aside from the average value of this potential diierence, the phase difference of the circuits may likewise be utilized for securing the desired compensating effect by composition of the load II as regards inductance and capacity, as above explained. It will likewise be appreciated that any desired lamp voltage curve may be attained or very closely approached by proper composition of the load II by deriving a reference voltage curve which is properly related to the desired lamp voltage curve and which relation may take account of and off-set the losses which may occur in the compensating connections. It will be understood that what has been said as to one intermediate position of the control handle will likewise apply to all other positions thereof, owing to the fact that the compensating control always compensates to the degree necessary to bring the voltage at the consum'ption circuit under all loads up to the required lamp voltage, or a very close approach thereto,

' for every position of the control handle.

In Fig. 3, the apparatus and connections are the same as those described in Fig. 2, the same reference characters designating the corresponding parts, except that in Fig. 3 the Winding 6 has more ampere-turns than the winding 6 of Fig. 3 and the winding 9' of Fig. 3 has less ampere-turns than the winding 9 of Fig. 2 and is reversed as to the winding 6'. In the case of Fig. 3, instead of compensating on the principle of raising the voltage of the consumption circuit to the required consumption circuit voltage curve, as in Fig.42, the excitation due to the winding 6' is made so large that if it acted alone, the voltage of the lamp circuit would be above the desired voltage for all positions of the control handle, The winding 9' being such as to always oppose the iiux due to the winding 6 and carrying a controlling current dependent upon the difference between the voltage of the consumption circuit and of the reference circuit will result in reducing the saturation ilux of the main reactor to such an amount as to bring the voltage at the consumption circuit down to the desired consumption circuit voltage; and this will occur in all il' positions of the control handle 8 giving the desired consumption voltage curve regardless of the load, as will be understood from the explanations made in Fig. l.

Fig. 4 shows the invention in its application to the control of the consumption circuit voltage particularly adapted for instances where the consumption circuit load is comparatively large. In Fig. 4 the parts similarly designated correspond to the same parts in Fig. 2. In Fig. 4 there is only one controlling direct current winding I6 on the main reactor core 3, the current for which is derived from the alternating current source I and controlled through an auxiliary controlling reactor having a core I'I. A transformer has a primary I8 connected to the source I and a secondary I8a which supplies current to a full wave rectifier I9 having anodes I9a and I9b and a cathode I9c. One terminal of the secondary I 8a is connected to a winding 20h on one of the outside legs of the reactor core I'I and is in turn connected to the anode I9b. The other terminal of the secondary I 8a is connected to a Winding 20a on the other outside leg of the core I'I and in turn is connected to the other anode I 9a. From a mid-point of the usual heating winding I 9d for the cathode, a connection extends to one terminal of the Winding I6 on the main reactor, the other terminal of the winding IG being connected to a mid tap of the secondary I8a.. 5

The windings 20a and 20h are so Wound on the legs of the core I'I that the flux thereof passes in a common direction through the middle leg of the core, as indicated by the arrows. The winding 6a on the middle leg I1 of the controlling reactor corresponds to the Winding 6 of Fig. 2 and is connected between the handle 8 and one terminal of the resistance l. The other winding 9a on the core I'I corresponds to the winding 9 on the'core 3 of Fig. 2 and is connected to the rectifying means i3a-I3d in the same way as in Fig. 2, the rectifying means being likewise connected to the points I4 and I5 of Fig. 4 in correspondence with the connections of Fig. 2 to the reference load and consumption circuit.

It will be appreciated from the explanations made in connection with Fig. 2 that adjustment of the control handle 8 will change the flux of the core I 'I by change of current through the winding Ba which in turn will control the output of the rectifier I9 to the control winding I6 of the main reactor. But, as explained in connection with Fig. 2, the current supplied to the winding I6 due to the control winding 6a alone, is not suiiicient to bring the voltage at the consumption circuit 2 up to the desired voltage curve; and the winding 9a acting cumulatively with the winding 6a is depended upon to raise the output oi the rectier I9 to the required amount to bring the voltage at the consumption circuit to the desired values along the consumption circuit voltage curve iordiil'erent positions oi' the control handle 8. This supplementary or compensating action by the winding 9a is, as already explained, due to utilization of the diil'erence between the potentials of the points Il and I5 of the consumption circuit and of the reference load. In the control system of Fig. 4, a comparatively small current through the winding 9a is sutlicient to produce the required compensation and the results obtained in this form of control give a greater renement of control and a closer approach of the consumption circuit voltage to that of the reference load voltage at all positions of the control handle 8.

In Fig. 5 the apparatus and connections are the same as those oi Fig. 4. However. in Fig. 5 the winding 6b on the middle leg of the core I1 is given more ampere turns than the winding 6a of Fig. 4 and the winding 9b oi' Fig. 5 is reversed with reference to the winding lb so that the ilux oi' winding 9b opposes that of the winding 6b, as well as opposing the ilux due to the windings 2|Ia and 20h. Thus, in Fig. 5, like in Fig. 3, the controlling action due the winding 8b alone is so great as to bring the flux and the resulting voltage of the consumption circuit above the desired consumption circuit voltage for the different positions of the control handle 8, whereas the winding 9b is depended vupon to bring the flux oi the core II down suillciently in its compensating action so that the current supplied to the winding I6 of the main reactor is oi the proper amount to give the required consumption circuit voltage for all positions of the control handle 0.

In both Figs. 4 and 5 an auxiliary cooperating controlling device 2| is shown connected in shunt to the rectiiler 9, being connected at points between the anode |9a and anode winding 20a and between the anode |9b and anode winding 2lb. 'I'he device 2| may bea non-inductive resistance, an inductive coil, or an impedance device oi any character to give the best cooperative results. It may advantageously be variable or adiustable but may be made of a ixed value selected to give desirable cooperation. The impedance device 2| aids in extending the range of control of the apparatus in the direction in whichiow voltage is applied to the consumption circuit and permits the auxiliary reactor controller to be made smaller than would otherwise be necessary.

This shunting impedance device is disclosed in various relationships to other apparatus and broadly claimed in my pending application, Serial No. 535.600, tiled May 7, 1931. It serves to cause an auxiliary current to pass through the windings 2|Ia and 20h during the alternate periods when those windings are inactive in supplying current to the consumption circuit. ing the winding 20a, and assuming that this supplies current to the load in a given direction which we may call positive, then during the alternate inactive periods, the impedance device 2| will cause or permit a current, which may be of comparatively small amount, to pass through the winding 20a in the reverse direction. This will be understood because during the alternate periods when the winding 20a is inactive in supplying current to the load, the winding 20h will be active in supplying current to the load and,

Considerby reason of the shunting impedance 2|, a small t part of the current supplied by the winding 2lb will pass through this shunt and through the winding `2M back to the source in a direction, say negative. and opposite to that of the current through winding 20a when it is supplying current to the load. The conditions thus set up in the winding 20a and its core, as regards flux and energy conditions, tends to establish in greater or lesser degree. as determined by the value of the impedance 2|, the conditions which would exist if the winding 20a and its core had not been subjected to inactive conditions as regards supply oi' energy to the output circuit. Consequently, when the winding 20a again becomes normally active, the amount oi' energy and current which this winding is permitted to deliver to the output circuit is correspondingly controlled and reduced. A similar condition exists with reference to the winding 2Gb and its core by the controlling eiect of the impedance device 2| in causing a controlling current to be passed through the winding 20h in a direction opposite to that of the normal load current therethrough; and this opposite controlling current will pass through the winding Zlib during the alternate inactive periods of the winding 20h. It has been found in practice that the controlling current due to the presence of the impedance device 2| may be made very small for obtaining the desired effect in the reduced control of the voltage applied to the consumption circuit. Thus, when the control handle 8 is moved in the direction to include a smaller amount of the resistance 1 and thereby supply a reduced current to the windings 6a or 8b, the shunting impedance 2| serves to give a cooperating amplifying eil'ect in still further reducing the current supplied to the rectiiler 9, giving the maximum cooperative effect at the lowest range of low voltage applied to the consumption circuit. When the handle 8 is moved to positions to include increasing amounts of the resistance 1, the cooperative eiiect of the shunting impedance 2| becomes less and less eiiective. At the higher values of load voltage, the impedance 2| continues to pass a reverse current alternately through the windings 20a and 20h; but the effect is then not material because the reactance of the windings 20a and 20h is then so low as to not be appreciably affected by the shunting current.

For the very best results the impedance 2| should preferably be adjusted to have a comparatively low value at low values of the voltage applied to the consumption circuit in order to permit the shunting current to have its highest iniluencc and then adjust it to have a comparatively high impedance at high values of voltage applied to the consumption circuit so that the shunting current would have a negligible value and effect. 'Ihe adjustment of this impedance can be controlled by, and simultaneously with, the adjustment of the control handle 8; but for simplicity and considering the advantages obtained when using a xed value of the impedance 2|, tiie renement of making the same adjustable would ordinarily be unnecessary. The fixed value would be arrived at by determining the amount ot the shunting control current at the lowest value of the consumption circuit voltage to give the desired effect under that condition and yet make it sumciently high to avoid any objectionable cilect at the high values of consumption circuit voltage.

In Fig. 6, instead of creating a special reference voltage as a standard for determining the controlling eiiect, the standard of reference is taken aovasso as that of the voltage between the control handle 8 and the other terminal of the resistance l includedin the circuit. In utilizing this adjustable voltage as the standard, the refinement of control and capability'of special adaptability is not as great as may be attained by the use of a specially made up load and creation of a special reference standard voltage, but is nevertheless of advantage as utilized herein by reason of its commercial practicability for some purposes. In applying the invention a voltage is derived from the consumption circuit voltage which reflects its change of voltage and which is properly related in comparative value and polarity to that of the standard voltage.

Thus in Fig. 6, wherein like reference character l ndicate similar parts of Fig. 4, the voltag of the direct current source 8 is assumed to be` ss than that of the supply lines from source l; and a direct current voltage is derived from the alternating current voltage of the consumption circuit which is properly functionally adapted to the variable standard voltage. Across the consumption circuit is connected an auto-transformer winding 22 having an adjustable contact 22a. Afterknowing the proper position of this contact or point of connection to the auto-transformer winding, this may be made a fixed connection. The 'leads from this point of connection and from one side of the consumption circuit are connected to opposed points of a rectifier of the above described bridge type having the rectiers 23a, 23h, 23o, and 23d in the arms of the bridge, although any suitable form of rectifier may be used. The other two opposite points of the bridge form the plus and minus terminals for delivering a direct current voltage which will correspond at all times to any change in voltage of the consumption circuit. In the lead wire connecting terminals of like polarity, say positive, of the source 5 and of the rectifier, is connected the cumulatively acting winding 9a of the auxiliary controlling reactor. The negative terminal of the rectifier is connected to the movable contact 8 of the control handle. Thus the voltage of the source 8, as adjusted by the control handle, is opposed in the circuit of the winding 8a to the voltage of the rectifier which voltage corresponds to the changes of the consumption circuit voltage. It follows that if these opposed voltages differ, a resultant current passes through the .winding 9a.

If the effect of the cumulative winding 9a be disregarded, the result would be that upon adjustment of the control handle 8, the resulting voltage applied to the consumption circuit would, for all adjusted positions, be below the ideal voltage curve. In order to secure the desired control, the direct current voltage delivered by the rectifier 23a-23d, must also be below the voltage of the source 5 as adjusted by the handle 8, even though this difference will be slight when the compensating effect of the winding 9a is considered. Under these assumptions, it follows that the cumulative winding 8a will carry a current from the source 5 through a comparatively high resistance by-pass 24 back to the control contact 8 and the source 5. This will, of course, result in raising the voltage of the consumption circuitfor any adjusted position of the handle 8 to nearly correspond with the standard reference voltage as determined by the adjusted position of the control handle 8 which, in this particular embodiment, is the voltage between the control handle 8 and one side of the source 5, being the positive side as indicated in the drawings. Thus, for any position of the control handle, the winding 9a will be subjected to such an amount of current as will cause the voltage applied to the consumption circuit to have an approximately constant ratio to the voltage as adjusted by the control handle 8. The by-pass resistance 24 is necessary owing to the fact that the compensating current in the winding 9a could not pass through the rectifier 23a-23d in the reverse direction. In the circuit of the winding 9a is also inserted a one way electric valve 25 of any suitable type so as to insure the current passing in the winding 9a in one direction only. If this valve were not present, a too rapid adjustment of the control handle 8 might otherwise cause the flow of a reverse current and interfere with the proper functioning of the apparatus owing to the fact that the time constant of the main reactor might differ widely from the time constant of the auxiliary controlling means or controlling reactor. For example, the main reactor controlling the consumption circuit is usually much slower in responding to the control than is the auxiliary controlling reactor.

The apparatus indicated in Fig. '7 is similar to that of Fig. 6 except the winding 6b of ther auxiliary reactor has more ampere-turns than the winding 6a of Fig. 6, whereas the winding 8b of Fig. '7 has less ampere-turns than the winding 9a of Fig. 6. Likewise, the winding 9b is so wound or connected as to cause its magnetomotive force to oppose that of the winding 8b. Also, the one way electric valve 25a in the circuit of the winding 9b is reversed so as to insure that the current will ilow only in one direction from the rectifier 23d-23d through the winding 9b to the source` 5. In this case the by-pass resistance 24 is unnecessary. In this application of the invention, the ampere-turns of the winding Si), as in Fig. 5, are of such values upon adjustment of the handle 8 that, disregarding the effect of the winding 9b, the voltage applied to the consumption circuit will always be higher than the desired ideal lamp voltage curve and always higher than the standard voltages imposed from the source 5 'by the different positions of the handle 8. Likewise the voltages delivered by the rectifier 23a-23d will be higher than the imposed standard voltage disregarding the eiect of the winding 9b and cause a current to pass through this winding to oppose the effect of the winding 8b and thus bring the voltages applied to the consumption circuit down to approximately coincide in proportional amounts with the standard voltage for all positions of the control handle 8.

Fig. 8 indicates apparatus similar to Fig. 6 as indicated by corresponding reference characters; but in Fig. 8 instead of utilizing a direct current source such as 5 for controlling the apparatus and as yielding the standard or pilot voltages, the control source is an alternating current source. For this purpose the transformer having the primary winding I8 is provided with an auxiliary secondary winding 28 which delivers current to the terminals of an adjustable resistance or inductance 2'l. An adjustable contact 21a engaging this resistance or inductance is connected to one terminal of a rectifier indicated of the bridge form and having rectifers 28a, 28h, 28e, and 28d in the arms of the bridge. From the opposite point of the bridge connection of the contact 21a, a lead 29 extends to one terminal of the adjustable impedance device 21.

desired, is imposed upon this rectiiier giving a corresponding direct current output voltage at the points of the bridge marked plus and minus in the drawings. The winding ta is connected across these terminals. likewise, the winding sa is connected in the circuit upon which is imposed the opposed voltages derived from the rectifier 23a-23d and oi the rectiiier 28a-20d. 'I'he operation is the same as that described with reference to Fig. 6, the output voltage of the rectifier 2id-28d corresponding to the standard or pilot voltage as imposed by adjustment oi' the contact 21a.

Fig. 9 is the same as Fig. 8 except it is modiiied to have the control winding 9b opposing the magnetomotive force oi' the winding 6b and cause the apparatus to operate on the principle oi' bringing the consumption circuit voltage down to be approximately the same as the standard reierence voltage by the opposing action oi the winding 9b of the auxiliary controller. This method of control is the same as that described with reference to Fig. 7. In Fig. 9, in view oi using an alternating current source for the pilot voltage and using a rectifier for converting the same, a shunt path of a comparatively high resistance 3l is provided across the circuit of the rectiiler 28d- 28d so as to permit the current which is always supplied in one direction from the rectifier 23a-23d, through the one way valve 25a, to have a return path after passing through the winding 9b through the resistance Il back to the rectiiler 23a-23d.

Pig. 10 shows the same apparatus as that oi Fig. 8 except an additional bridge connected type rectier lla, Nb, llc, and lid. is introduced i'or individually supplying current to the winding 6a of the auxiliary controlling reactor, the rectiiler IIa-Sid receiving its imposed voltage from the alternating source as controlled by the adjustable contact 21a. This provision of an independent supply ior the control winding Ba gives a little better regulation than the form of Fig. 8 as less duty is imposed upon the rectiiier 28a-28h; and it likewise insures that the current in winding M cannot be reversed, as might otherwise be caused by the diilerence in time constants of dierent portions of the apparatus. By the use of this auxiliary rectier for supplying the winding 6a, the one way valve 25 would then ordinarily be unnecessary.

Fig. 11 indicates the same apparatus as Fig. 10 except that the ampere-turns of the windings 6b and 9b are so related and likewise their direction oi' turns that the operation is based upon the mode described with reference to Figs. 3, 5, 7, and 9.' In the case of Eg. 11 the resistance 24 of Fig. 10 is omitted or transferred to form the resistance 30 connected across the line on the other side of the winding 9b so that the exciting current in this winding from the rectiiler 23a- 23d will ilnd a path for its return thereto after passing through the winding 9b.

In Fig. 12 the apparatus is similar to that disclosed in Figs. 10 and 11 except that the ampereturns of the windings 6o and 9c are modied in relation to each other so that instead of working on the principle of the previously described apparatus of raising the consumption circuit voltages up to the ideal lamp voltage or bringing them down from values above the ideal lamp voltages, there are enough turns in the control winding 6c to give the nearest values obtainable of the consumption circuit voltage to the standard voltage 'Ihus an alternating current voltage. adiustedas and then either raise it or lower it to approximately coincide with the voltage selected as the standard by passing a current through the winding 8c in either one direction or in the reverse direction according to whether the consumption circuit voltage requires to be raised or lowered for a particular position of the control handle. 'Rius in Fig. 12 current may pass in either direction through the winding 9c depending upon whether the output voltage oi the rectifier 23a-23d is higher or lower than the output voltage o! the rectifier 28a- 28d in order to bring the consumption voltage to the desired amount. In this case both the shunting resistances 24 and 3l are used so that one or the other may form a return path for the current to the rectifier that happens to be active in supplying current to the winding It'. This method of control by reversal of current through the winding 9c could also be utilized by making corresponding changes in other disclosures oi this application.

Fig. 13 is similar to Fig. 12 and is introduced as one example oi how the auxiliary controlling reactor may be modied in the various disclosures hereof. Instead ot using a single core, two

separately acting cores 32, 32a are provided. These cores are shown ci simple rectangular form. One arm of the core 22 carries the anode winding 20c and on one leg of the core 32a is mounted the other anode winding 20e. The control winding 6c oi Fig. 12 is divided into two parts 8d and 6e and placed respectively on legs of the cores 32 and 32a and are connected in series with each other across output terminals of the rectiiler lila-Bld. Similarly, the winding c of Fig. 12 is divided into two parts 9d and 9e which are placed respectively on other arms oi the cores 32 and 32a and are connected in series with each other in the circuit o! the opposed controlling voltages. Although Fig. 13 shows the adapta tion of Fig. 12 to this form of division o! the auxiliary controlling reactor, it is evident that the reactors of the other tlgures of the drawings may be similarly sub-divided and various other changes made in the forms of the cores and relationship of the windings.

It will be understood that the accompanying drawings and description disclose embodiments of this invention in simple forms oi apparatus for the purpose oi simplicity and ready understanding and that the structure of the various parts may be widely varied from the typical forms indicated. Likewise, the invention may be embodied in various modifications and relationship of the parts for particular installations and purposes without departing from the scope of the invention. It will also be appreciated that the form oi the desired consumption circuit voltage curve may be made such as to suit the particular purposes and character of consumption circuit load by proper composition oi the reference load as to its resistance, inductance and capacity, where a specially created reference voltage is utilized.

I claim:

1. Electric controlling apparatus comprising a consumption circuit, a reference voltage circuit, adjustable means for imposing on the reference voltage circuit a series of values of voltages over a wide range and for imposing on the consumption circuit a series of values of voltages below those imposed on the reference voltage circuit, and auxiliary means for raising the values of the voltages oi.' the consumption circuit to approach those of the reference voltage circuit.

2. Electric controlling apparatus comprising a consumption circuit, a reactor having a controlling winding for changing the voltage of the consumption circuit over a series of values, and a second winding on said reactor acting in opposition to said controlling winding for reducing said series of values to a lower range of values. 3. The method of obtaining a series of voltages of different values applied to a consumption circuit which comprises imposing a series of values of voltages on the consumption circuit lower than the desired values, creating a series of desired reference voltages of different values, and raising the voltages of the consumption circuit to approach the respective reference voltages.

4. 'I'he combination of an alternating current circuit, an alternating current consumption circuit, a reactor having a winding in series between said circuits, a direct current winding on said reactor, means comprising an adjustable direct current source supplying current to said winding for varying the reactance of said reactor over a Wide range and thereby varying the voltage of the consumption circuit over a wide range, means for deriving direct current voltages from the consumption circuit corresponding in values to change of the alternating current voltages of the consumption circuit, and a winding responsive to the differences between the voltages of said adjustable direct current source and the direct current voltages derived from the consumption circuit for bringing the voltages of the consumption circuit to relatively conform to those of said direct current source at each condition of adjustment.

5. An alternating current supply cir'cuit, a consumption circuit supplied with alternating current from said supply circuit, a reactor having a winding in series between said circuits, adjustable means comprising a saturating winding on said reactor vfor changing the reactance of said reactor and'fthe voltage of the consumption circuit over a widev range and for yielding a series of corresponding reference voltages as a. standard, and auxiliary means comprising an additional winding on said reactor affected by the relative departure of the voltages of the consumption circuit from said series of reference voltages respectively for causing the voltages of the consumption circuit to relatively conform to the series of reference voltages respectively.

6. Electric controlling apparatus comprising a consumption circuit, adjustable means comprising a reactor having a saturating winding for changing the voltage of the consumption circuit over a wide range and for creating a series of reference voltages over a wide range conforming to a series of desired Values, and auxiliary electromagnetic means comprising an additional Winding on said reactor for causing the voltage of the consumption circuit to relatively conform to that of the reference voltage throughout the range of control.

7. Electric controlling apparatus comprising ak consumption circuit, means comprising a reactor having a saturating Winding and an adjustable handle for changing the voltage of the consumption circuit over a wide range, auxiliary means controlled by the movement of said handle for creating a reference voltage over a wide range conforming to a series of desired values, and means comprising an additional winding on said reactor for causing the voltage of the consumption circuit to relatively approach and conform to that of the reference voltage for each position of' said handle.

. 8. Electric controlling apparatus comprising a consumption circuit, a reference load circuit, means comprising a reactor having a saturating winding for changing the voltages applied to said circuits, and auxiliary means comprising a winding on said reactor responsive to the relative departure of the voltages of the consumption circuit voltages from the reference load circuit voltages respectively for causing the voltage of the consumption circuit to relatively conform to that of the reference load circuit.

9. Electric controlling apparatus comprising a consumption circuit, a reference voltage circuit, adjustable means vcomprising a reactor having a saturating winding for imposing on the reference voltage circuit a series of values of voltages over a wide range and for imposing on the consumption circuit a series of values of voltages above desired values, and means comprising an additional winding on said reactor for reducing the values of the voltages of the consumption circuit to relatively conform to those of the reference voltage circuit.

10. An alternating current supply circuit, a consumption circuit supplied with alternating current from said supply circuit, a reactor having a Winding in series between said circuits, adjustable means for aecting said reactor to apply a series of voltages to the consumption circuit below desired values, and to establish a series of reference voltages of desired values, and means comprising an additional winding on said reactor affected by the difference between the voltage of the consumption circuit and the corresponding reference voltage for increasing the voltages at the consumption circuit to the desired values.

11. An alternating current supply circuit, a consumption circuit supplied with alternating current from said supply circuit, a reactor having a winding in series between said circuits, adjustable means for affecting said reactor t apply a series of voltages to the consumption circuit above desired values, and means comprising an additional winding on said reactor for decreasing said voltages to the desired values.

l2. The method of obtaining a series of voltages of different values applied to a consumption circuit which comprises imposing a series of values of voltages on the consumption circuit higher and lower in portions of the series than the desired values, creating a series of reference voltages, and lowering and raising the voltages of the consumption circuit in different portions of the series of voltages to conform relatively to the respective reference voltages.

13. Electric controlling apparatus comprising a consumption circuit, a reference circuit having a xed load, a device for changing the voltage applied to the consumption circuit, a device for changing the voltage applied to the reference load circuit for imposing a series of desired voltages thereon, a common adjustable means for affecting both of said devices for effecting the change in said voltages, and auxiliary control means for adjusting the consumption circuit voltages to relatively conform respectively to the reference load voltages.

14. Electric controlling apparatus comprising a consumption circuit, a reactor for controlling the voltage applied to said circuit, adjustable means for controlling said reactor, a reference circuit having a fixed load, means controlled by said first named means for imposing on said reference circuit a series of voltages of desired values, and additional means affected by the difference between the voltages of said circuits for controlling said reactor for brinlinl the voltages of the consumption circuit to relatively conform to those of the reference circuit respectively.

15. Electric controlling apparatus comprising a consumption circuit, means comprising a reactor having'a saturating winding for changing the voltage applied to said circuit over a wide range and for forming a corresponding series of reference voltages as a standard, and means comprisng an additional compensating winding on said reactor affected by the relative departure of the voltages of the consumption circuit from said series of reference voltages respectively for causing the voltages of the consumption circuit to relatively conform to said series of reference voltages respectively.

16. An alternating current source, an alternating current consumption circuit, a direct current source, means for deriving a series of desired reference voltages from said direct current source and for varying over a wide range the voltage of said consumption circuit, means for deriving a direct current from said consumption circuit, and means responsive to dierence in voltages between said reference voltages and the voltages derived from said consumption circuit respectively for relatively conforming the voltages of the consumption circuit to said reference voltages respectively.

17. An alternating current source, an alternating current consumption circuit, a reactor having a winding in series between said source and said circuit, a direct current source, means for deriving a series of desired reference voltages from said direct current source and for varying over a wide range the voltage of said consumption circuit, means for deriving a direct current from said consumption circuit, and means comprising a controlling winding responsive to difference in voltages between said reference voltages and the voltages derived from said consumption circuit respectively for relatively conforming the voltages of the consumption circuit to said reference voltages respectively.

18. An alternating current source, an alternating current consumption circuit, a reactor having a winding in series between said source and said circuit, a saturating winding on said reactor, a rectifier for supplying current to said saturating winding, means for supplying alternating current to said rectifier, a reactor having a winding connected in series between said means and said rectifier, means for deriving a direct current from said consumption circuit, means for deriving a series oi desired direct current reference voltages, and means comprising a winding on said second named reactor responsive to the diierence in voltages between said reference voltages and the voltages of the direct current derived from said consumption circuit respectively for relatively conforming the voltages of the consumption circuit to said reference voltages respectively.

19. An alternating current source, an alternating current consumption circuit, a reactor having a winding in series between said source and said circuit, a saturating winding on said reactor, a rectifier for supplying current to said saturating winding, means for supplying alternating current to said rectifier, a reactor having a winding connected in series between said means and said rectier, means for deriving a to the difference in voltages between said reference voltages and the voltages of the direct current.derived from said consumption circuit respectively for relatively conforming the voltages of the consumption circuit to said reference voltages respectively, and an impedance device connected in shunt between terminals of said rectiiier.

20. An alternating current source, an alternating current consumption circuit, a reactor having a winding in series between said source and said circuit, a saturating winding on said reactor, a rectifier for supplying current to said saturating winding, means for supplying alternating current to said rectifier. a reactor having a winding connected in series between said means and said rectiiier, a saturating winding on said last named reactor, means for deriving a direct current from said consumption circuit, means for deriving a series of desired direct current reference voltages and for supplying current in said saturating winding on said last named reactor, and means comprising an additionalwinding on said last named reactor responsive to the difference in voltages between said reference voltages and the voltages of the direct current derived from said consumption circuit respectively for relatively conforming the voltages of the consumption circuit to said reference voltages respectively.

21. An alternating current source, an alternating current consumption circuit, a reactor having a winding in series between said source and said circuit, a saturating winding on said reactor, a rectifier for supplying current to said saturating winding. means for supplying alternating current to said rectifier, a reactor having a winding connected in series between said means and said rectiner, a saturating winding on said last named reactor, means for deriving a direct current from said consumption circuit. means for deriving a series of desired direct current reference voltages and for supplying current to said saturating winding on said last named reactor, and means comprising an additional winding on said last named reactor responsive to the difference in voltages between said reference voltages and the voltages of the direct current derived from said consumption circuit respectively for relatively conforming the voltages of the consumption circuit to said reference voltages respectively, said additional winding acting cumulatively with said saturating winding on said last named reactor.

22. An alternating current source, an alternating current consumption circuit, a reactor having a winding in series between said source and said circuit, a saturating winding on said reactor, a rectifier for supplying current to said saturating winding, means for supplying alternating current to said rectifier, a reactor having a winding connected in series between said means and said rectifier. a saturating winding on said last named reactor, means for deriving a direct current from said consumption circuit, means for deriving a series of desired direct current reference voltages and for supplyin current to said saturating winding on said last named reactor, and means comprising an additional winding on said last named reactor responsive to the difference in voltages between said reference volt- 75 ages and the voltages of the direct current derived from said consumption circuit respectively for relatively conforming the voltages of the consumption circuit to said reference voltages respectively, said additional Winding acting in opposition to said saturating winding on said last named reactor.

23. Electric controlling apparatus comprising a consumption circuit, means comprising a reactor having a saturating winding for changing the voltage applied to said circuit over a wide range and for forming a corresponding series of reference voltages as a standard, and means comprising an additional compensating winding on said reactor affected by the relative departure of the voltages of the consumption circuit from said series of reference voltages respectively for causing the voltages of the consumption circuit to relatively conform to said series of reference voltages respectively, said additional winding acting cumulatively with said saturating winding.

24. Electric controlling apparatus comprising a consumption circuit, means comprising a reactor having a saturating winding for changing the voltage applied to said circuit over a wide range and for forming a corresponding series of reference voltages as a standard, and means comprising an additional compensating winding on said reactor affected by the relative departure of the voltages of the consumption circuit from said series of reference voltages respectively for causing the voltages of the consumption circuit to relatively conform to said series of reference voltages respectively, said additional winding acting in opposition to said saturating winding.

25. An alternating current source, an alternating current consumption circuit, a reactor having a winding in series between said source and said circuit, a saturating winding on said reactor, a rectifier for supplying current to said saturating winding, means for supplying alternating current derived from said source to said rectifier, a reactor having a winding connected in series between said means and said rectifier, a saturating winding on said last named reactor, means for deriving a direct current from said source for exciting said saturating winding on said last named reactor and for varying the voltage thereof, means for deriving a direct current from said consumption circuit having a voltage corresponding thereto, and means comprising an additional winding on said last named reactor responsive to the difference in voltages between said variable direct current voltages derived from said source and the direct current voltages derived from said consumption circuit for relatively conforming the voltages of the consumption circuit to said variable voltages derived from said source.

26, An alternating current source, an alternating current consumption circuit, a reactor having a winding in series between said source and said circuit, a saturating winding on said reactor, a rectifier for supplying current to said saturating winding, means for supplying alternating current derived from said source to said rectifier, a reactor having a winding connected in series between said means and said rectifier, a saturating winding on said last named reactor, means for deriving a direct current from said source for exciting said saturating winding on said last named reactor and for #Stylus the voltage thereof, means for deriving a direct current from said consumption circuit having a voltage corresponding thereto, and means comprising an additional winding on said last named reactor responsive to the difference in voltages between said variable direct current voltages derived from said source and the direct current voltages derived from said consumption circuit for relatively conforming the voltages of the consumption circuit to said variable voltages derived from said source, said additional winding acting cumulatively with said saturating winding on said last named reactor.

27. An alternating current source, an alternating current consumption circuit, a reactor having a winding in series between said source and said circuit, a saturating winding on said reactor, a rectifier for supplying current to said saturating Winding, means for supplying alternating current derived from said source to said rectifier, a reactor having a winding connected in series between said means and said rectifier, a saturating winding on said last named reactor, means for deriving a direct current from said source for exciting said saturating winding on said last named reactor and for varying the voltage thereof, means for deriving a direct current from said consumption circuitI having a voltage corresponding thereto, and means comprising an additional winding on said last named reactor responsive to the difference in voltages between said variable direct current voltages derived from said source and the direct current voltages derived from said consumption circuit for relatively conforming the voltages of the consumption circuit to said variable voltages derived from said source, said additional winding acting in opposition to said saturating winding on said last named reactor.

28. Electric controlling apparatus comprising a consumption circuit, adjustable means comprising a reactor having a saturating winding for changing the voltage of the consumption circuit over a wide range and for creating a series of reference voltages over a wide range conforming to a series of desired values, means responsive to the relative departure of the voltages of the consumption circuit from said series of reference voltages respectively, and an additional winding on said reactor controlled by said last named means for causing the voltage of the consumption circuit to relatively conform to that oi' the reference voltage throughout the range of control.

29. Electric controlling apparatus comprising a consumption circuit, means comprising a reactor having a saturating winding and an adjustable handle for changing the voltage of the consumption circuit over a wide range, auxiliary means controlled by the movement of said handle for creating a reference voltage over a wide range conforming to a series of desired values, means responsive to the relative departure of the voltages of the consumption circuit from said sexies of reference voltages respectively, and an additional winding on said reactor controlled by said last named means for causing the voltage of the consumption circuit to relatively conform to that of the reference voltage for each position of said handle.

FRANK G. LOGAN. 

